Radon Determination

[Orville Cypret 441-6411 <CYPRETOW@lmus.com>]

I'm trying to find a simple method for discriminating between environmental Rn 
contamination and uranium + daughters in the field.  We use Berthold hand & foot 
monitors, and Eberline PCM-1B and PCM-2 half-body monitors and they frequently 
alarm due to Rn.  Raising the alarm setpoint isn't an option.  We have a large 
inventory of gaseous, liquid, and solid uranium hexafluoride here so the 
presence of Rn is not unexpected.  Generally, we don't believe the source of the 
Rn is the enrichment process system since we do not detect HF when we're having 
Rn problems and it doesn't seem reasonable for the Rn to leak out of the process 
piping without UF6 also leaking out and forming HF.  The environment is 
typically around 100 degrees F (or more) and resolving an alarm may take 30-60 
minutes.  If a person is experiencing heat stress, we don't want to delay them 
at the monitoring point any longer than is absolutely necessary.

I need to teach our technicians how to discriminate between Rn and uranium + 
(short lived) daughters since our response for the two is different.  Although 
this sounds like it ought to have a simple answer, in a uranium enrichment plant 
it's hard to do.  We have a wide selection of Ludlum and Bicron survey 
instruments available to the technicians for field measurements.  Any 
suggestions would be appreciated.

Orville Cypret
Paducah Gaseous Diffusion Plant
Lockheed Martin Utility Services
cypretow@lmus.com
502/441-6173